Double-sealed high-temperature resistant DC ignitor for use with wood pellet burner assemblies

ABSTRACT

Embodiments of the inventive concept provide a double-sealed high-temperature resistant DC ignitor for use with a wood pellet burner assembly. The DC ignitor includes a non-heating element portion. The non-heating element portion is connected to at least one of a battery or an AC to DC electrical transformer attached to the wood pellet burner assembly. A heating element is connected to the non-heating element portion, and extends by at least one inch into a combustion region of the wood pellet burner assembly. The heating element portion is configured to be heated by power received from the battery or the AC to DC electrical transformer. The DC ignitor provides safe, reliable, and fast combustion of wood pellets that congregate in a combustion region of the wood pellet burner assembly.

RELATED APPLICATION DATA

This application is a continuation-in-part of co-pending, commonly-ownedU.S. patent application Ser. No. 15/454,680, filed Mar. 9, 2017, whichis a continuation-in-part of commonly-owned U.S. patent application Ser.No. 14/120,192, filed May 2, 2014, which claims the benefit ofcommonly-owned U.S. provisional patent application Ser. No. 61/818,841,filed May 2, 2013, which are hereby incorporated by reference.

TECHNICAL FIELD

The present invention relates generally to wood pellet-burningbarbecues, and, more particularly, to a DC ignitor and a wood pelletburner for use with such barbecues.

BACKGROUND

Wood pellet-burning barbecues are popular for outdoor cooking.Conventional wood pellet-burning barbecues, of the type described inU.S. Pat. No. 4,823,684, employ a motor-driven auger to provide ameasured feed of wood pellets into a combustion region where the pelletsare burned to provide heat and smoke to cook food.

An aspect of such conventional wood pellet-burning barbecues is that themotor that drives the auger can require a steady supply of significantpower as provided by, for example, an AC electrical power source. Whileconvenient in outdoor settings of many homes, the required AC power orsuch barbecues has limited their portability and use where convenient ACpower is not available such as at parks, sporting events, some campingareas, etc.

Moreover, conventional AC ignitors used in wood pellet-burner units areunreliable and have a short life-span. The ignitor is often the firstcomponent of a wood pellet-burner unit to fail. This is partly due tothe harsh high-temperature environment under which ignitors aresubjected, but can also be attributed to moisture build up, directcontact with the wood pellets, and materials by which they areconstructed. Such disadvantages lead to frequent tripping of GroundFault Interrupters (GFIs), which create a significant annoyance at best,and dangerous safety issues at worst for users. Conventional ignitorssuffer from other problems such as long heat up times—as high as twominutes or more—to reach a temperature that is capable of igniting thewood pellets, and human shock safety problems.

Accordingly, a need remains for an improved wood pellet-burning unitignitor, and for wood pellet burner assemblies that provide highlyreliable and efficient operation of a wood pellet-burning barbecue,thereby enhancing the portability of wood pellet-burning barbecues.Embodiments of the inventive concept address these and other limitationsin the prior art.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a side elevation, with portions broken away, of aprior art wood pellet-burning barbecue in accordance with variousembodiments of the present inventive concept.

FIG. 2 illustrates side elevation of an implementation of a pelletburner assembly in accordance with various embodiments of the presentinventive concept.

FIGS. 3 and 4 are sectional side views of the pellet burner assembly ofFIG. 2 separately illustrating pellet fuel and airflow, respectively.

FIG. 5 illustrates a plan view into a hopper of the pellet burnerassembly of FIG. 2.

FIGS. 6 and 7 are top and bottom views of a perforated slide of thepellet burner assembly of FIG. 2.

FIG. 8 illustrates a side elevation of a barbecue with the pellet burnerassembly of FIG. 2.

FIG. 9 illustrates a circuit schematic diagram of the pellet burnerassembly in accordance with some embodiments.

FIG. 10 illustrates another circuit schematic diagram of the pelletburner assembly in accordance with various embodiments of the presentinventive concept.

FIG. 11 illustrates yet another circuit schematic diagram of the pelletburner assembly in accordance with various embodiments of the presentinventive concept.

FIG. 12 illustrates side elevation of an implementation of a pelletburner assembly including a double-sealed high-temperature resistant DCignitor in accordance with various embodiments of the present inventiveconcept.

FIG. 13 illustrates a plan view of a section of the DC ignitor of FIG.12 taken along lines XIII-XIII.

FIG. 14 illustrates side elevation of another implementation of a pelletburner assembly including another double-sealed high-temperatureresistant DC ignitor in accordance with various embodiments of thepresent inventive concept.

FIG. 15 illustrates a plan view of a section of the DC ignitor of FIG.14 taken along lines XV-XV.

FIG. 16 illustrates side elevation of yet another implementation of apellet burner assembly including yet another double-sealedhigh-temperature resistant DC ignitor in accordance with variousembodiments of the present inventive concept.

FIG. 17 illustrates a plan view of a section of the DC ignitor of FIG.16 taken along lines XVII-XVII.

FIG. 18 illustrates side elevation of still another implementation of apellet burner assembly including a wood pellet auger, and including adouble-sealed high-temperature resistant DC ignitor in accordance withvarious embodiments of the present inventive concept.

FIG. 19 illustrates side elevation of yet another implementation of apellet burner assembly including a sliding floor hopper, and including adouble-sealed high-temperature resistant DC ignitor in accordance withvarious embodiments of the present inventive concept.

The foregoing and other features of the inventive concept will becomemore readily apparent from the following detailed description, whichproceeds with reference to the accompanying drawings.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Reference will now be made in detail to embodiments of the inventiveconcept, examples of which are illustrated in the accompanying drawings.The accompanying drawings are not necessarily drawn to scale. In thefollowing detailed description, numerous specific details are set forthto enable a thorough understanding of the inventive concept. It shouldbe understood, however, that persons having ordinary skill in the artmay practice the inventive concept without these specific details. Inother instances, well-known methods, procedures, components, circuits,and networks have not been described in detail so as not tounnecessarily obscure aspects of the embodiments.

It will be understood that, although the terms first, second, etc. maybe used herein to describe various elements, these elements should notbe limited by these terms. These terms are only used to distinguish oneelement from another. For example, a first cellular network could betermed a second cellular network, and, similarly, a second cellularnetwork could be termed a first cellular network, without departing fromthe scope of the inventive concept.

It will be understood that when an element or layer is referred to asbeing “on,” “coupled to,” or “connected to” another element or layer, itcan be directly on, directly coupled to or directly connected to theother element or layer, or intervening elements or layers may bepresent. In contrast, when an element is referred to as being “directlyon,” “directly coupled to,” or “directly connected to” another elementor layer, there are no intervening elements or layers present. Likenumbers refer to like elements throughout. As used herein, the term“and/or” includes any and all combinations of one or more of theassociated listed items.

The terminology used in the description of the inventive concept hereinis for the purpose of describing particular embodiments only and is notintended to be limiting of the inventive concept. As used in thedescription of the inventive concept and the appended claims, thesingular forms “a,” “an,” and “the” are intended to include the pluralforms as well, unless the context clearly indicates otherwise. It willalso be understood that the term “and/or” as used herein refers to andencompasses any and all possible combinations of one or more of theassociated listed items. It will be further understood that the terms“comprises” and/or “comprising,” when used in this specification,specify the presence of stated features, integers, steps, operations,elements, and/or components, but do not preclude the presence oraddition of one or more other features, integers, steps, operations,elements, components, and/or groups thereof.

FIG. 1 is a side elevation, with portions broken away, of a prior artpellet-burning barbecue 8 described in U.S. Pat. No. 4,823,684. Barbecue8 is configured to place the top of a pan 10 at a convenient workingheight above the ground, through legs 12 secured to and extendingdownwardly from the base of the pan 10. For convenience of moving, ifdesired, wheels 14 are provided rotatably journaled on the base of twoof the legs in the barbecue. For moving purposes, the barbecue may bepartially raised utilizing handles 16 connected to the pan wherebyground contact is solely through those legs having wheels 14, thebarbecue then being rollable to the position desired.

Pan 10 includes a bottom 20 and opposed side and end walls 22, 24 joinedto bottom 20. The top of the pan may be reinforced as by framing 25. Pan10 is open at the top. If desired, a hinged cover 26 may be includedconnected by hinges 28 to pan 10. The cover is swingable between aclosed position where the cover closes off the top of the barbecue pan,as shown in FIG. 2, and an open position where the cover is swung to oneside to expose the barbecue pan interior, as shown in FIG. 1. The covermay further include a ventilating hood as shown at 30.

A burner assembly 32 extends underneath the barbecue pan fromapproximately centrally of the pan to a position on one side thereof. Inthe specific embodiment of the invention disclosed, the burner assembly33 includes an elongate housing 34 of substantially rectangular, i.e.,square, cross section, and including top, bottom, and opposed side wallsindicated at 36, 37, 38, and 39. The ends of the housing are closed offby end walls 41, 42.

Top wall 36 has a circular aperture 44 adjacent one end. Suitablysecured as by welding within the housing and communicating with thisaperture is a cylindrical fire pot 46 which is open at its top andclosed at its bottom. The interior of the fire pot faces upwardly, andcommunicates with the interior of pan 10 through aperture 48 in bottom20 of the pan.

The cylindrical wall of the fire pot contains perforations 50. With theconstruction described, the housing walls define a chamber extendingalong the interior of the housing and this chamber communicates throughperforations 50 with the interior of the fire pot. Extending along theinterior of housing 34 is a tube 52 having one end secured as by weldingto the cylindrical wall of pot 46. The wall of the pot is cut out toprovide an opening therein which communicates with the interior of tube52. The opposite end of the tube is appropriately secured to end wall 42of the housing.

Mounted within tube 52 is an elongate auger 54 terminating in a shaft55. The shaft extends through wall 42 where it is supported in a bearingassembly 56. An electric gear motor 58 mounted on the end of the housingthrough bracket 60 has its output shaft connected through drive coupling62 with the end of auger shaft 55.

Tube 52 is open at 64 and a wall 66 extending up from this openingprovides a throat for the channeling of pellet fuel downwardly onto theauger to be fed thence by operation of the auger through the auger tube.A hopper 68 is supported on top of housing 34 which holds a supply ofpellet fuel. The top wall of the housing is suitably cut away to placethe base of the hopper in direct communication with the top of thethroat defined by wall 66.

Supported on the underside of housing 34 approximately underneath thehopper is an electrically operated blower 70 having its discharge endconnected through duct 74 with the chamber defined along the length ofthe interior of housing 34. A shutter 76 supported on the blowerassembly by a pivot mounting 78 is adjustable to vary the degree ofclosure of intake 79 to the blower and, in this way, the amount ofairflow produced by the blower through its discharge opening along thelength of the housing.

The housing is supported on the underside of the pan through bolts 80,which extend upwardly from top wall 36 and through accommodating boresprovided in the bottom of the pan, with securement completed using nutsscrewed onto the protruding ends of the bolts.

Gasket material 84 may be provided intermediate the top wall of thehousing and the underside of the barbecue pan. Additional securement ofthe housing beneath the barbecue pan may be provided by securing aportion of the hopper to the side of the pan in an appropriate manner.

Disposed within the interior of the barbecue pan somewhat upwardly fromthe top of the fire pot is a nonperforate, metallic, baffle pan or plateshown at 90 including a floor and a raised shoulder extending about itsperimeter. The baffle plate extends in a region disposed over the top ofthe fire pot and outwardly from this region to edges disposed inwardlysomewhat from the side walls of the barbecue pan. The baffle plate isremovably supported in this position as by legs 92 which may be joinedeither to the underside of the baffle pan or to the base of the barbecuepan with their opposite extremities unsecured. A food-support means orgrill 96 is mounted within the interior of the barbecue pan and directlyadjacent the top thereof, such grill being supported on support lugs 98joined to the side walls of the barbecue pan.

To start up the barbecue, the grill is removed and the baffle pan tippedto an upright position which exposes the top of the fire pot. A smallamount of wood pellets, i.e., a handful, are then placed in the fire pottogether with combustible material such as paper, and the like. This isthen lit, and combustion allowed to proceed for a short period of timesuch as two minutes or so. The baffle pan and grill may then be replacedin their operative positions, the air blower started, and the augermotor started. This produces forced-air circulation down the interior ofhousing 34 with the air blowing inwardly into the fire pot to supportcombustion of the material therein. The operation of the auger producesa gradual feed of replacement pellets to the fire pot, replacingmaterial as such is burned. Normally a warm-up period of only a fewminutes is required alter replacement of the grill and before cookingmay proceed.

With the barbecue operating, food to be cooked may be placed on thegrill. The blower produces forced-air circulation within the interior ofthe barbecue pan with heated air coming from the fire pot movingupwardly and around the baffle plate and thence circulating against andthrough the grill. Cooking may be performed with the cover in the closedposition or with the cover open. With the cover closed, oven-likeconditions are produced within the barbecue, and with the cover open,grill-like conditions are produced. The baffle plate on being heatedradiates heat upwardly. Drippings from any food cooked are preventedfrom falling into the fire pot by the baffle plate which collects suchmaterial. With cooking concluded, the auger is stopped which stops feedof pellet material to the fire pot. With stoppage of pellet feed andwith the blower turned off, combustion in the pot soon terminates. FIGS.2-4 illustrate a DC wood pellet burner assembly 100 operable, forexample, as a general substitute for or alternative to burner assembly32 described with reference to prior art pellet-burning barbecue 8 ofFIG. 1.

Pellet burner assembly 100 includes a pellet hopper 102 that receivesand stores a supply of fuel (e.g., wood) pellets 104 (illustratedfiguratively in FIG. 3—as is known in the art, pellets 104 aresignificantly smaller than illustrated) and feeds them through a pelletintake 106 and onto a perforated slide 108 in a burn tube 110 to be fedtoward a combustion region 112. In the illustrated implementation,hopper 102 includes at least one inclined face 114 to provide gravityfeed of pellets 104 into intake 106. Pellet burner assembly 100 includesa face 116 for mounting to a side 118 of a barbecue, such as a barbecue120 (FIG. 8).

Barbecue 120 is shown without support legs, as it would be configured inone portable configuration for use on a tabletop or other like surface,for example. It will be appreciated, however, that barbecue couldalternatively be mounted on legs or a cart, for example.

In the illustrated implementation, face 116 is contiguous with hopper102. It will be appreciated, however, that the mounting structure forsecuring pellet burner assembly 100 to barbecue could alternatively bedistinct from hopper 102. Also, face 116 is illustrated as beingsubstantially vertical to conform to a corresponding side 118 ofbarbecue 120 so that pellet burner assembly 100 may be secured tobarbecue 120 by a pair of nuts and bolts 121 (one shown), or more, thatextend through corresponding apertures (not shown) in the side 122 ofbarbecue 120.

Barbecue 120 includes a pan 124 with an interior volume 126 over which agrill 128, or other food-supporting structure (e.g., grate, nonperforatesurface, etc.) extends to support food to be cooked such as by hotsmoking or other indirect heat cooking. Side 118 includes an aperture(not shown) sized to receive burn tube 110 in a fitted relationship tothat burn tube 110 extends into and combustion region 112 is positionedwithin the interior volume 126 of pan 124. A baffle pan or plate 130,substantially similar in operation to baffle pan or plate 90 (FIG. 1),extends partially across pan 122 in spaced relation above burn tube 110and below grill 128.

Pellet burner assembly 100 further includes a DC ignitor 140, such as aglow plug, having a heating element 142 that extends into combustionregion 112 to ignite pellets 104, a DC fan 144 is positioned to direct aflow of air through perforations 145 (FIGS. 5-7) of perforated slide 108to combustion region 112, and a DC power source 146, such as avehicle-grade 12-volt battery.

FIG. 9 is a schematic circuit diagram illustrating electrical system 150of pellet burner assembly 100. Battery 146 is connected between a bodygrounding lug 152 and a user-operable power switch 154 that turnselectrical system on or off. When on, power switch 154 provides power tofan 144 and to an ignitor activating switch 156, such as a normally openswitch that is operable with a push-button 158 and is connected toignitor 140. Upon a user switching power switch 154 to on, fan 144 isactivated and power is delivered to ignitor activating switch 154. Auser may then press push-button 158 for a period of time (e.g.,approximately 2 minutes) to activate ignitor 140 until pellets 104 incombustion region 112 are ignited. The user may then release push-button158, deactivating ignitor 140.

Once ignited, the air flow provided by fan 144 allow pellets 104 incombustion region 112 continue to burn and to be replenishedautomatically as additional pellets 104 drop through intake 106. Pelletburner assembly 100 includes a pellet feed control door 160 that isslidable along one face (e.g., face 116) to control the rate of flow ofpellets 104 into combustion region 112, thereby controlling the cookingtemperature of barbecue 120. In addition, feed control door 160functions to close intake 106 so that burning of pellets 104 can bestopped by stopping the flow of pellets 104 into combustion region 112.In the implementation illustrated in FIGS. 3 and 4, feed control door160 is in threaded engagement with a positioning screw 162 that a usercan turn by way of a knob 164 to slide door 160 up or down.

As a result, such a wood pellet burner assembly allows a woodpellet-burning barbecue to be used where AC power is not available, suchas at parks, sporting events, some camping areas, etc., and cansignificantly enhance the portability of wood pellet-burning barbecues.

In one implementation, a pellet burner assembly according to the presentinvention includes a gravity-feed pellet fuel hopper positioned inalignment with a pellet fuel intake and a perforated pellet fuel slidethat extends to a combustion region. A DC ignitor has a heating elementthat extends into the combustion region, and a DC fan is positioned todirect a flow of air through the perforated pellet fuel slide and intothe combustion region. A DC power source, such as a vehicle-grade12-volt battery, is coupled to and powers the DC ignitor and the DC fan.Such a wood pellet burner assembly allows a wood pellet-burning barbecueto be used where AC power is not available, such as at parks, sportingevents, some camping areas, etc., and can significantly enhance theportability of wood pellet-burning barbecues.

FIG. 10 illustrates another circuit schematic diagram of a wood pelletburner assembly 1000 in accordance with various embodiments of thepresent inventive concept. The wood pellet burner assembly 1000 caninclude an alternating current (AC) to direct current (DC) electricaltransformer 1005. The AC to DC electrical transformer 1005 can receiveAC mains power 1055 via lines 1010. The AC to DC electrical transformer1005 can output a DC+ voltage potential on line 1045 and a DC− voltagepotential on line 1050.

A double-sealed high-temperature resistant direct current (DC) ignitor1015 is provided for use with the wood pellet burner assembly 1000. TheDC ignitor 1015 can include a non-heating element portion 1020. Thenon-heating element portion 1020 can be connected to a battery (e.g.,146 of FIG. 9) or to the AC to DC electrical transformer 1005. The AC toDC transformer 1005 can be attached to the wood pellet burner assembly1000. The ignitor 1015 can include a heating element 1030 connected tothe non-heating element portion by way of a heating rod 1065. Theheating element 1030 can include a resistive heating coil 1060. Theheating element 1030 can extend by at least one inch into a combustionregion of the wood pellet burner assembly 1000, thereby providing moresurface area to contact wood pellets disposed in a combustion region ofthe wood pellet burner assembly 1000, as further described below. Theheating element portion 1030 can be heated by power received from thebattery (e.g., 146 of FIG. 9) or the AC to DC electrical transformer1005. The DC ignitor can include a nut 1040 or other suitable transitionsection between the heating rod 1065 and the non-heating element portion1020.

The double-sealed high-temperature resistant DC ignitor 1015 can includean ignitor housing 1025. The ignitor housing 1025 can contain theheating element 1030, the heating rod 1065, and the non-heating elementportion 1020. The heating element 1030 can include a heating coil 1060disposed in the heating element 1030 within the ignitor housing 1025,which when powered, heats up the heating element 1030, including theignitor housing 1025 proximate to the heating element 1030. The heatingrod 1065 can be disposed within the ignitor housing 1025 and connectedto the heating coil 1060 in the heating element 1030. The DC ignitor1015 can include a first seal 1070 disposed within the ignitor housing1025 at a terminal end of the heating rod 1065. The DC ignitor 1015 caninclude a second seal 1075 disposed within the ignitor housing 1025 at aterminal end of the non-heating element portion 1020.

In some embodiments, the ignitor housing 1025 is at least partiallycomprised of a ceramic. In some embodiments, the ignitor housing 1025 isentirely comprised of the ceramic. In some embodiments, the ceramic canbe a high-temperature resistant ceramic. In some embodiments, the outerhousing 1205 is at least partially comprised of a ceramic. In someembodiments, the outer housing 1205 is entirely comprised of theceramic. In some embodiments, the ceramic can be a high-temperatureresistant ceramic. For example, the ceramic can include at least one ofHafnium carbide (HfC), Tantalum carbide (TaC), Niobium carbide (NbC),Zirconium carbide (ZrC), Hafnium nitride (HfN), Hafnium boride (HfB2),Zirconium boride (ZrB2), Titanium boride (TiB2), Titanium carbide (TiC),Niobium boride (NbB2), Tantalum boride (TaB2), Titanium nitride (TiN),Zirconium nitride (ZrN), Silicon carbide (SiC), Vanadium carbide (VC),Tantalum nitride (TaN), or Niobium nitride (NbN).

In some embodiments, the ignitor housing 1025 is at least partiallycomprised of a superalloy including at least nickel and chromium. Insome embodiments, the ignitor housing 1025 is entirely comprised of thesuperalloy including at least nickel and chromium. In some embodiments,the ignitor housing 1025 is at least partially comprised of a superalloysuch as Inconel®. In some embodiments, the ignitor housing 1025 is atleast partially comprised of a superalloy such as Inconel® 600, Inconel®617, Inconel® 625, Inconel® 690, Inconel® 718, and/or Inconel® X-750. Insome embodiments, the ignitor housing 1025 is entirely comprised of thesuperalloy such as Inconel®. In some embodiments, the ignitor housing1025 is entirely comprised of the superalloy such as Inconel® 600,Inconel® 617, Inconel® 625, Inconel® 690, Inconel® 718, and/or Inconel®X-750.

In some embodiments, the first seal 1070 and the second seal 1075 areeach comprised of a fluoroelastomer such as Viton®. In some embodiments,the first seal 1070 and/or the second seal 1075 are comprised ofcopolymer having at least one of ethylene, tetrafluoroethylene (TFE), orperfluoromethylvinyl ether (PMVE). The double seals prevent moisture andother contaminants such as acid from the wood pellet fuel from enteringand corroding the heating coil 1060 and other internal elements of theDC ignitor 1015. In comparison to conventional ignitors, whichproblematically cause GFIs to often trip due to moisture and othercontaminants seeping into the ignitor, the double-sealedhigh-temperature resistant DC ignitor 1015 provides an extremelyreliable ignitor function that can withstand the harsh conditions of awood pellet burning unit in outside environments without tripping GFIs.Moreover, the useful life span of the DC ignitor disclosed hereinsignificantly exceeds that of conventional wood pellet burner ignitors.

In some embodiments, the non-heating element portion 1020 is connectedto a positive terminal of the battery (e.g., 146 of FIG. 9) or to apositive terminal of the AC to DC electrical transformer 1005. In someembodiments, the ignitor housing 1025 is connected to a negativeterminal of the battery (e.g., 146 of FIG. 9) or to a negative terminalof the AC to DC electrical transformer 1005. In some embodiments, anegative terminal of the battery (e.g., 146 of FIG. 9) or the negativeterminal of the AC to DC electrical transformer 1005 is connected to agrounding lug (e.g., 152 of FIG. 9) that is directly connected to thewood pellet burner assembly 1000.

FIG. 11 illustrates yet another circuit schematic diagram of a pelletburner assembly 1000 in accordance with various embodiments of thepresent inventive concept. Some elements have the same referencenumerals as described in embodiments above, and therefore, a detaildescription of such elements is not necessarily repeated.

The AC to DC electrical transformer 1005 can be connected between a bodygrounding lug 1125 and a user-operable power switch 1105 that turns theelectrical system on or off. The non-heating element portion 1020 can beconnected to the AC to DC electrical transformer 1005 via theuser-operable ignitor switch 1110 and via the user-operable power switch1105. When on, the power switch 1105 can provide power to a fan 1120 andto an ignitor activating switch 1110, such as a normally open switchthat is operable with a push-button 1115, and is connected to the DCignitor 1015. When turned on, the user-operable power switch 1105 canprovide power from the AC to DC electrical transformer 1005 to theuser-operable ignitor switch 1110 and the heating element 1030 via theuser-operable power switch 1105. Upon a user switching power switch 1105to on, the fan 1120 is activated and power can be delivered to theignitor activating switch 1110. A user may then press push-button 1115for a period of time (e.g., approximately 30 seconds) to activate the DCignitor 1015 until pellets (e.g., 104 of FIG. 3) in the combustionregion (e.g., 112 of FIG. 3) are ignited. The user may then releasepush-button 1115, deactivating the DC ignitor 1015. The heating element1030 can receive power from the AC to DC electrical transformer 1005responsive to a press of the push-button 1115 that is connected to theuser-operable ignitor switch 1110.

Once ignited, the air flow provided by the fan 1120 allow the pellets104 in the combustion region 112 continue to burn and to be replenishedautomatically as additional pellets 104 drop through the intake (e.g.,106 of FIG. 3).

FIG. 12 illustrates side elevation of an implementation of a pelletburner assembly 1200 including a double-sealed high-temperatureresistant DC ignitor 1270 in accordance with various embodiments of thepresent inventive concept. FIG. 13 illustrates a plan view of a sectionof the DC ignitor 1270 of FIG. 12 taken along lines XIII-XIII Referenceis now made to FIGS. 12 and 13. Some elements have the same referencenumerals as described in embodiments above, and therefore, a detaildescription of such elements is not necessarily repeated.

In some embodiments, the heating element 1030 extends through a pelletfuel slide 1230 of the wood pellet burner assembly 1200. The DC ignitor1270 can include a tubular outer housing 1205 surrounding a mid sectionof the ignitor housing 1025. A plurality of threads 1260 can be disposedin the tubular outer housing 1205. A plurality of set screws 1210 can bedisposed in the corresponding plurality of threads 1260. The set screws1210 can hold the ignitor housing 1025 within the tubular outer housing1205 without the ignitor housing 1025 directly touching inner walls ofthe tubular outer housing 1205. In some embodiments, an annularcombustion air intake opening 1265 can be disposed at a terminal end ofthe tubular outer housing 1205. The annular combustion air intakeopening 1265 can receive combustion air 1220 from outside the tubularouter housing 1205. The tubular outer housing 1205 can guide thecombustion air 1220 over the ignitor housing 1025 to cool the ignitorhousing 1025. The tubular outer housing 1205 can guide the combustionair 1220 toward the heating element 1030 to assist in combusting woodpellets 1245 disposed in the combustion region 1275 of the pellet burnerassembly 1200.

In some embodiments, the plurality of set screws 1210 includes a firstset screw 1210 a, a second set screw 1210 b, and a third set screw 1210c. The first set screw 1210 a can extend radially from the ignitorhousing 1025 in a first direction. The second set screw 1210 b canextend radially from the ignitor housing 1025 in a second direction thatis 120 degrees offset relative to the first set screw 1210 a. The thirdset screw 1210 c can extend radially from the ignitor housing 1025 in athird direction that is 120 degrees offset relative to the second setscrew 1210 b. The tubular outer housing 1205 can be connected to thepellet fuel slide 1230 such that the ignitor housing 1025 does notdirectly touch the pellet fuel slide 1230. For example, the tubularouter housing 1205 can be welded to the pellet fuel slide 1230 with weldmaterial 1215. The DC ignitor 1270 can extend into a central base areaof the combustion region 1275 of the wood pellet burner assembly 1200.More specifically, the heating element 1030 of the DC ignitor 1270 canextend by at least one inch, as shown at 1240, into the combustionregion 1275, thereby exposing a greater surface area to contact with thewood pellets 1245, and thereby speeding the initiation of combustion ofthe wood pellets 1245.

FIG. 14 illustrates side elevation of another implementation of a pelletburner assembly 1400 including another double-sealed high-temperatureresistant DC ignitor 1470 in accordance with various embodiments of thepresent inventive concept. FIG. 15 illustrates a plan view of a sectionof the DC ignitor 1470 of FIG. 14 taken along lines XV-XV. Reference isnow made to FIGS. 14 and 15. Some elements have the same referencenumerals as described in embodiments above, and therefore, a detaildescription of such elements is not necessarily repeated.

In some embodiments, the heating element 1030 extends through a pelletfuel slide 1230 of the wood pellet burner assembly 1400. The DC ignitor1470 can include a tubular outer housing 1403 surrounding a mid sectionof the ignitor housing 1025. An ignitor holding flange 1415 can beconnected to the tubular outer housing 1403. A plurality of threads 1460can be disposed in the tubular outer housing 1403. The plurality ofthreads 1460 can extend into the ignitor holding flange 1415. Aplurality of set screws 1420 can be disposed in the correspondingplurality of threads 1460. The ignitor holding flange 1415 can receivethe plurality of set screws 1420. The set screws 1420 can hold theignitor housing 1025 within the tubular outer housing 1403 without theignitor housing 1025 directly touching inner walls of the tubular outerhousing 1403. In some embodiments, a plurality of combustion air intakeopenings 1405 can be disposed in the tubular outer housing 1403. Thecombustion air intake openings 1405 can receive combustion air 1410 fromoutside the tubular outer housing 1403. The tubular outer housing 1403can guide the combustion air 1410 over the ignitor housing 1025 to coolthe ignitor housing 1025. The tubular outer housing 1403 can guide thecombustion air 1410 toward the heating element 1030 to assist incombusting wood pellets 1245 disposed in the combustion region 1275 ofthe pellet burner assembly 1400.

In some embodiments, the plurality of set screws 1420 includes a firstset screw 1420 a, a second set screw 1420 b, and a third set screw 1420c. The first set screw 1420 a can extend radially from the ignitorhousing 1025 in a first direction. The second set screw 1420 b canextend radially from the ignitor housing 1025 in a second direction thatis 120 degrees offset relative to the first set screw 1420 a. The thirdset screw 1420 c can extend radially from the ignitor housing 1025 in athird direction that is 120 degrees offset relative to the second setscrew 1420 b. The tubular outer housing 1403 can be connected to thepellet fuel slide 1230 such that the ignitor housing 1025 does notdirectly touch the pellet fuel slide 1230. For example, the tubularouter housing 1403 can be welded to the pellet fuel slide 1230 with weldmaterial 1215. The DC ignitor 1470 can extend into a central base areaof the combustion region 1275 of the wood pellet burner assembly 1400.More specifically, the heating element 1030 of the DC ignitor 1470 canextend by at least one inch, as shown at 1240, into the combustionregion 1275, thereby exposing a greater surface area to contact with thewood pellets 1245, and thereby speeding the initiation of combustion ofthe wood pellets 1245.

FIG. 16 illustrates side elevation of yet another implementation of apellet burner assembly 1600 including yet another double-sealedhigh-temperature resistant DC ignitor 1670 in accordance with variousembodiments of the present inventive concept. FIG. 17 illustrates a planview of a section of the DC ignitor 1670 of FIG. 16 taken along linesXVII-XVII. Reference is now made to FIGS. 16 and 17. Some elements havethe same reference numerals as described in embodiments above, andtherefore, a detail description of such elements is not necessarilyrepeated.

The DC ignitor 1670 of the pellet burner assembly 1600 incorporatesfeatures of both of the DC ignitor 1270 of FIG. 12 and the DC ignitor1470 of FIG. 14. For example, the DC ignitor 1670 includes the pluralityof combustion air intake openings 1405 and the annular combustion airintake opening 1265. Accordingly, the DC ignitor 1670 can receive thecombustion air 1220 and the combustion air 1410, which enhances the flowof the combustion air over the ignitor housing 1025 and toward theheating element 1030 to assist in combusting the wood pellets 1245disposed in the combustion region 1275 of the pellet burner assembly1600.

FIG. 18 illustrates side elevation of still another implementation of awood pellet burner assembly 1800 including a wood pellet auger 1805, andincluding a double-sealed high-temperature resistant DC ignitor 1870 inaccordance with various embodiments of the present inventive concept. Itwill be understood that the DC ignitor 1870 can be any of the DCignitors described herein. Some elements have the same referencenumerals as described in embodiments above, and therefore, a detaildescription of such elements is not necessarily repeated. The auger 1805can provide a measured feed of the wood pellets 1245 into the combustionregion 1275. The heating element 1030 can initiate combustion of thewood pellets 1245 provided by the auger 1805. The wood pellet burnerassembly 1800 can include the AC to DC electrical transformer 1005,which can be connected to the DC ignitor 1870 to provide DC power to theDC ignitor 1870.

FIG. 19 illustrates side elevation of yet another implementation of apellet burner assembly 400 including a sliding floor hopper 402, andincluding a double-sealed high-temperature resistant DC ignitor 1970 inaccordance with various embodiments of the present inventive concept. Itwill be understood that the DC ignitor 1970 can be any of the DCignitors described herein. Some elements have the same referencenumerals as described in embodiments above, and therefore, a detaildescription of such elements is not necessarily repeated. The slidingfloor hopper 402 can provide a measured feed of wood pellets 422 intothe combustion region 490. The heating element 1030 can initiatecombustion of the wood pellets 422 provided by the sliding floor hopper402. The wood pellet burner assembly 400 can include the AC to DCelectrical transformer 1005, which can be connected to the DC ignitor1970 to provide DC power to the DC ignitor 1970.

The sliding floor hopper 402 can include an upper loading section 405having an opening 408 through which wood pellets (e.g., 425 and 420) canbe received. The sliding floor hopper 402 can include a staging section410 in which the wood pellets can be staged for automatic and periodicfeeding on a continuous basis into the burner section 415.

The sliding floor hopper 402 can include a sliding floor 430. Thesliding floor 430 can be caused to laterally oscillate in a continuouscycle, which can automatically feed the burner section 415. For example,the sliding floor 430 can be caused to slide from a back position to aforward position, and then can be caused to return to the back position,and so forth. The wood pellets (e.g., 425) can accumulate near a backregion 428 of the staging section 410 when the sliding floor 430 is inthe back position. Then, when the sliding floor 430 transitions from theback position to the forward position, the pellets 425 near the backregion 428 can be pushed forward toward a front region 412 of thestaging section 410. Simultaneously, when the sliding floor 430transitions to the forward position, some of the wood pellets (e.g.,420) can be pushed off of a staging surface 414 of the staging section410, thereby causing some of the wood pellets (e.g., 422) to be pushedover a staging edge 416, and to tumble onto a fire grate 460 and intoburner section 415.

The sliding floor hopper 402 can include motor 450, a cam 445, aconnecting shaft 435, a connecting pin 440, and the sliding floor 430.The motor 450 can be a gear motor, for example. The motor 450 can be alow-torque motor such as in the range of 5 to 15 Inch-pounds. Forexample, the motor 450 can be a 10 Inch-pound low-torque motor. The cam445 can transform rotary motion of the motor 450 into a substantiallylinear motion of the connecting shaft 435. In an alternative embodiment,the cam 445 can be coupled directly to the sliding floor 430 such thatit directly oscillates the sliding floor 430 in the lateral directions(not shown). The connecting shaft 435 can cause the sliding floor 430 tolaterally oscillate by use of the connecting pin 440. The motor 450 canhave a fan 455 attached thereto to provide cooling to the motor 450. Thefan 455 can be spun by the rotary motion of the motor 450.

Within the burner section 415 of the wood pellet burner unit 400, thefire grate 460 can be at least partially disposed below the staging edge416 to receive the wood pellets (e.g., 422) as they are pushed off thestaging edge 416. The wood pellets 422 can travel down the fire grate460 and form near a lower region 418 of the fire grate 460 and theburner section 415. The DC igniter 1970 can be disposed near the lowerregion 418 and can cause the wood pellets 422 that congregate near thelower region 418 to ignite. The DC igniter 1970 can be manually and/orelectrically controlled.

A combustion fan 475 can be attached to the burner section 415 of thewood pellet burner unit 400. The combustion fan can provide air 480,including oxygen, to fan and energize the flames 490, and to keep theburner section 415 efficiently burning the wood pellets (e.g., 418). Theair 480 can be pushed by the combustion fan 475 through a vent oropening 485 into the burner section 415, through holes 495 in the firegrate 460, and toward the wood pellets (e.g., 418), thereby fanning andenergizing the flames 490 so that the wood pellets continue to burn.

One of skill in the art will recognize that the concepts taught hereincan be tailored to a particular application in many other ways. Inparticular, those skilled in the art will recognize that the illustratedexamples are but one of many alternative implementations that willbecome apparent upon reading this disclosure.

Embodiments are described herein, and illustrated in the drawings, interms of functional blocks, units and/or modules. Those skilled in theart will appreciate that these blocks, units and/or modules can bephysically implemented by electronic (or optical) circuits such as logiccircuits, discrete components, microprocessors, hard-wired circuits,memory elements, wiring connections, and the like.

Having described and illustrated the principles of the inventive conceptwith reference to illustrated embodiments, it will be recognized thatthe illustrated embodiments can be modified in arrangement and detailwithout departing from such principles, and can be combined in anydesired manner And although the foregoing discussion has focused onparticular embodiments, other configurations are contemplated. Inparticular, even though expressions such as “according to an embodimentof the invention” or the like are used herein, these phrases are meantto generally reference embodiment possibilities, and are not intended tolimit the inventive concept to particular embodiment configurations. Asused herein, these terms can reference the same or different embodimentsthat are combinable into other embodiments.

Consequently, in view of the wide variety of permutations to theembodiments described herein, this detailed description and accompanyingmaterial is intended to be illustrative only, and should not be taken aslimiting the scope of the inventive concept. What is claimed as theinvention, therefore, is all such modifications as may come within thescope and spirit of the following claims and equivalents thereto.

The invention claimed is:
 1. A high-temperature resistant direct current(DC) ignitor for use with a wood pellet burner assembly, comprising: anon-heating element portion, wherein the non-heating element portion isconnected to at least one of a battery or an alternating current (AC) toDC electrical transformer attached to the wood pellet burner assembly; aheating element portion connected to the non-heating element portion,and configured to extend into a combustion region of the wood pelletburner assembly, wherein the heating element portion is configured to beheated by power received from the at least one of the battery or the ACto DC electrical transformer; an outer housing surrounding a mid sectionof an ignitor housing; a plurality of threads disposed in the outerhousing; and a plurality of set screws disposed in the correspondingplurality of threads, and configured to hold the ignitor housing withinthe outer housing without the ignitor housing directly touching innerwalls of the outer housing, wherein: the heating element portion isconfigured to extend through a pellet fuel slide of the wood pelletburner assembly; the DC ignitor is disposed in a substantiallyhorizontal orientation; the wood pellet burner assembly includes a DCfan positioned to direct a flow of air in a substantially horizontaldirection along the length of the DC ignitor, through perforations inthe pellet fuel slide and into the combustion region; the AC to DCelectrical transformer is configured to power the DC ignitor and the DCfan; the wood pellet burner assembly includes a body grounding lug, auser operable power switch, and a user-operable ignitor switch incommunication between the AC to DC electrical transformer and the DCignitor; and the user-operable power switch, when turned on, isconfigured to provide power from the at least one of the battery or theAC to DC electrical transformer to the user-operable ignitor switch andthe heating element portion via the user-operable power switch.
 2. Thehigh-temperature resistant DC ignitor for use with a wood pellet burnerassembly of claim 1, wherein the ignitor housing is at least partiallycomprised of a ceramic.
 3. The high-temperature resistant DC ignitor foruse with a wood pellet burner assembly of claim 2, wherein the ceramicincludes at least one of Hafnium carbide (HfC), Tantalum carbide (TaC),Niobium carbide (NbC), Zirconium carbide (ZrC), Hafnium nitride (HfN),Hafnium boride (HfB2), Zirconium boride (ZrB2), Titanium boride (TiB2),Titanium carbide (TiC), Niobium boride (NbB2), Tantalum boride (TaB2),Titanium nitride (TiN), Zirconium nitride (ZrN), Silicon carbide (SiC),Vanadium carbide (VC), Tantalum nitride (TaN), or Niobium nitride (NbN).4. The high-temperature resistant DC ignitor for use with a wood pelletburner assembly of claim 1, wherein the outer housing is at leastpartially comprised of a ceramic.
 5. The high-temperature resistant DCignitor for use with a wood pellet burner assembly of claim 4, whereinthe ceramic includes at least one of Hafnium carbide (HfC), Tantalumcarbide (TaC), Niobium carbide (NbC), Zirconium carbide (ZrC), Hafniumnitride (HfN), Hafnium boride (HfB2), Zirconium boride (ZrB2), Titaniumboride (TiB2), Titanium carbide (TiC), Niobium boride (NbB2), Tantalumboride (TaB2), Titanium nitride (TiN), Zirconium nitride (ZrN), Siliconcarbide (SiC), Vanadium carbide (VC), Tantalum nitride (TaN), or Niobiumnitride (NbN).
 6. The high-temperature resistant DC ignitor for use witha wood pellet burner assembly of claim 1, wherein the ignitor housing isat least partially comprised of a superalloy.
 7. The high-temperatureresistant DC ignitor for use with a wood pellet burner assembly of claim6, wherein the superalloy includes at least one of Inconel® 600,Inconel® 617, Inconel® 625, Inconel® 690, Inconel® 718, or Inconel®X-750.
 8. The high-temperature resistant DC ignitor for use with a woodpellet burner assembly of claim 1, wherein: the wood pellet burnerassembly includes a wood pellet fuel hopper positioned in alignment witha pellet fuel intake and the pellet fuel slide, which extends to thecombustion region of the wood pellet burner assembly; and the DC ignitorextends into a central base area of the combustion region of the woodpellet burner assembly.
 9. The high-temperature resistant DC ignitor foruse with a wood pellet burner assembly of claim 1, wherein theuser-operable ignitor switch includes a push-button.
 10. Thehigh-temperature resistant DC ignitor for use with a wood pellet burnerassembly of claim 9, wherein the heating element portion is configuredto receive power from the at least one of the battery or the AC to DCelectrical transformer responsive to a press of the push-button that isconnected to the user-operable ignitor switch.
 11. The high-temperatureresistant DC ignitor for use with a wood pellet burner assembly of claim1, wherein the AC to DC electrical transformer is connected between thebody grounding lug and the user-operable power switch.
 12. Thehigh-temperature resistant DC ignitor for use with a wood pellet burnerassembly of claim 1, wherein: the user-operable power switch, whenturned on, is configured to provide power to the DC fan and to theuser-operable ignitor switch; and the user-operable ignitor switch isconnected to the DC ignitor.
 13. The high-temperature resistant DCignitor for use with a wood pellet burner assembly of claim 1, whereinthe non-heating element portion is connected to the at least one of thebattery or the AC to DC electrical transformer via the user-operableignitor switch and via the user-operable power switch.
 14. Thehigh-temperature resistant DC ignitor for use with a wood pellet burnerassembly of claim 1, further comprising: the ignitor housing; a heatingcoil disposed in the heating element portion within the ignitor housing;a heating rod disposed within the ignitor housing and connected to theheating coil in the heating element portion; a first seal disposedwithin the ignitor housing at a terminal end of the heating rod; and asecond seal disposed within the ignitor housing at a terminal end of thenon-heating element portion.
 15. The high-temperature resistant DCignitor for use with a wood pellet burner assembly of claim 14, whereinthe first and second seals are each comprised of a fluoroelastomerincluding a copolymer having at least one of ethylene,tetrafluoroethylene (TFE), or perfluoromethylvinyl ether (PMVE).
 16. Ahigh-temperature resistant direct current (DC) ignitor for use with awood pellet burner assembly, comprising: a non-heating element portion,wherein the non-heating element portion is connected to at least one ofa battery or an alternating current (AC) to DC electrical transformerattached to the wood pellet burner assembly; a heating element portionconnected to the non-heating element portion, and configured to extendinto a combustion region of the wood pellet burner assembly, wherein theheating element portion is configured to be heated by power receivedfrom the at least one of the battery or the AC to DC electricaltransformer; an outer housing surrounding a mid section of an ignitorhousing; a plurality of threads disposed in the outer housing; and aplurality of set screws disposed in the corresponding plurality ofthreads, and configured to hold the ignitor housing within the outerhousing without the ignitor housing directly touching inner walls of theouter housing, wherein: the heating element portion is configured toextend through a pellet fuel slide of the wood pellet burner assembly;the DC ignitor is disposed in a substantially horizontal orientation;the wood pellet burner assembly includes a DC fan positioned to direct aflow of air in a substantially horizontal direction along the length ofthe DC ignitor, through perforations in the pellet fuel slide and intothe combustion region; the AC to DC electrical transformer is configuredto power the DC ignitor and the DC fan; the wood pellet burner assemblyincludes a body grounding lug, a user operable power switch, and auser-operable ignitor switch in communication between the AC to DCelectrical transformer and the DC ignitor; and wherein the non-heatingelement portion is connected to the at least one of the battery or theAC to DC electrical transformer via the user-operable ignitor switch.17. A high-temperature resistant direct current (DC) ignitor for usewith a wood pellet burner assembly, comprising: a non-heating elementportion, wherein the non-heating element portion is connected to atleast one of a battery or an alternating current (AC) to DC electricaltransformer attached to the wood pellet burner assembly; a heatingelement portion connected to the non-heating element portion, andconfigured to extend into a combustion region of the wood pellet burnerassembly, wherein the heating element portion is configured to be heatedby power received from the at least one of the battery or the AC to DCelectrical transformer; an outer housing surrounding a mid section of anignitor housing; a plurality of threads disposed in the outer housing; aplurality of set screws disposed in the corresponding plurality ofthreads, and configured to hold the ignitor housing within the outerhousing without the ignitor housing directly touching inner walls of theouter housing, wherein the heating element portion is configured toextend through a pellet fuel slide of the wood pellet burner assembly;an ignitor holding flange connected to the outer housing, wherein theplurality of threads extend into the ignitor holding flange, and whereinthe ignitor holding flange is configured to receive the plurality of setscrews; and an annular combustion air intake opening at a terminal endof the outer housing, wherein the annular combustion air intake openingis configured to receive combustion air from outside the outer housing,wherein the outer housing is configured to guide the combustion air overthe ignitor housing to cool the ignitor housing, and wherein the outerhousing is configured to guide the combustion air toward the heatingelement portion to assist in combusting wood pellets disposed in thecombustion region of the pellet burner assembly.